APACHE II Score Calculator

Calculate the APACHE II score for ICU patients to estimate severity of illness and hospital mortality.

Age (years)

Temperature (°C)

Mean Arterial Pressure (mmHg)

Heart Rate (bpm)

Respiratory Rate (/min)

FiO₂

PaO₂ or A-aDO₂ (mmHg)

Arterial pH

Serum Sodium (mEq/L)

Serum Potassium (mEq/L)

Serum Creatinine (mg/dL)

Hematocrit (%)

WBC (×10³/μL)

Glasgow Coma Scale (3–15)

Chronic Health Points

How to Use the APACHE II Calculator

Enter physiological values from the worst in the first 24 hours of ICU admission.
Select the FiO2 level and enter the corresponding oxygenation value.
Enter GCS (3–15), age, and chronic health status.
Click 'Calculate' to see the score and mortality estimate.

Cas d'utilisation

•ICU severity of illness assessment.
•Comparing outcomes across patient populations.
•Research and benchmarking in critical care.

Formule

APACHE II = Acute Physiology Score (12 variables) + Age points + Chronic health points. Range 0–71.

Questions fréquemment posées

What is the APACHE II score?

The Acute Physiology and Chronic Health Evaluation II (APACHE II) is a severity-of-disease scoring system for patients admitted to the ICU. It uses 12 routine physiological measurements plus age and chronic health status.

How is APACHE II interpreted?

Higher scores correlate with higher hospital mortality. Score <5: <4%; 5–9: 7–12%; 10–14: 15–25%; 15–19: ~40%; ≥20: >55% estimated mortality.

Medical disclaimer

This calculator is for educational purposes only. It does not replace professional medical evaluation. Always consult a qualified healthcare provider for clinical decisions.